Centrifugal fltjid-pressure-generating apparatus



C. H. SMOOT. CENTRIFUGAL FLUID PRESSURE GENERATING APPARATUS.

APPLICATION FILED MAY 20. 1920.

Patented Dec. 7, 1920.

INVENTOR. Uflmlw fv S UNITED STATES PATENT OFFICE.

CHARLES H. SMOOT, OF SOUTH ORANGE, NEW JERSEY, ASSIGNOR TO RATEAU BATTU SMOOT ENGINEERING CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

CENTRIFUGAL FIU ID-PRESSURE-GENERATING APPARATUS.

Specification of Letters Iatent'.

Patented Dec. *7, 1920.

Application filed'May 20, 1920. Serial No. 382,995.

to the square of the speed of rotation of the impeller. In the construction of this element, the means I have devised obviates pressure fluctuations, as well as errors or departures between a uniform ratio of speed to pressure.

, It is well known inthe art that a centrifugal pressure creating element such as a centrifugal pump or similar device, produces approximately a fluid pressure in pro portion to the square of the speed and that such pressure varies, increasing or decreasing with the quantity of fluid passing through the impeller.

' A centrifugal fan or pump is arrangedprimarily to pass a volume of fluid from a lowerto a higher pressure and its features of'construction are proportioned for economical power consumption in the production of fluid under pressure. -When' used as a speed meter, or centrifugal governor, the rotary pressure creating element is not passing'any material volume and if proportioned in the same manner as would be a centrifugal pump or blower, the pressure delivered'is notstrictly in proportion to the speed of rotation and also varies-with the quantity of fluid passing, and when such'quantity is restricted, a fluctuating pressure unsuitable for metering or regulation is developed.

By means of the pressure creating centrifugal. element which I have. invented,

these disadvantages are obviated and my apparatus produces a pressure free from fluctuations, having a fixed ratio between speed and pressure when no volume is passing through the machine other than a small amount of inevitable leakage.

To obtain this result, I employ an impeller and easing so proportioned that it maintains a definite diameter andradial depth of annular ring of the fluid rotating at the speed of the shaft. Iprovide means which prevent the impeller communicating a rotary motion to the fluid beyond a predetermined lcglstlance inside or outside of the impeller or A simple embodiment of one form of my invention will suffice to make clear to those skilled in the art the manner in which the improvement is applied in practice.

The accompanying drawings-Figures I, II, and IIIshow Fig. I, a vertical cross-sectlon through my apparatus; Fig. II, a view in vertical plan of wheel 2 of Fig. I; and Fig. III, a view in vertical plan of wheel 2 modified.

Referring to Figs. I and II shaft 1 revolves in ournal 3. 2 is a wheel rigidly attached to shaft 1 by means of nut 30. 66 are pro-. ject ing vanes attached to wheel 2. 5-5 is I a rlng having radial perforations 31-31. Wheel 2 rotates in casing 7, which is closed by cover plate 4. Annular chamber 8 is partitioned by ring 5-5. 9 is a pipe for the dis- InFig. III, wheel 2 is shown. with symbols corresponding to Fig. II. WVheel 2 has a shroud 32 with radial perforations 33- L The operation of my apparatus is substantially as follows Fluid is introduced through radial perforations 12 and 13 into the rotating element comprised of wheel 2 and vanes 6. The fluid is discharged by vanes 6 in such a manner that it rotates in a relatively small space between the end of vanes 6 and ring 5. The air escaping through ring 5 is discharged through radial perforations 3131 in such a way that'in the outer portion of annular chamber 6 there is no appreciable rotary motion of the fluid.

It will be seen that the fluid within shell 10 is nowhere exposed to moving metal. and can acquire no tendency to rotate by frictional contact with the impeller, as is the case with centrifugal pumps and the like.

Thefunction of ring 5 and perforations diameter, that can behdisplaced in its path 31-31 is to destroy therotary motion of all fluid leaving the impeller after it has reached this ring, without conversion to pressure. This is the reverse of What is done in the construction o f -a pump, in whichfor reasons'of economyall velocities, especially those of discharge from the impeller are converted into pressure. Ring 5 de-' stroys the rotary velocities with correspondlng loss of energy and with almost complete non-conversion into pressure, thus obliging the apparatus tocreate pressure only'by virtue of the rotating ring of fluid of definite internal and external. diameter.

In Fig. III, wheel 2 carries a shroud 32 with perforations 33-33. By means of this construction, the influence of ring.5 to set up'internalswirls and eddies within the volume of fluid located from periphery of vanes 6 to ring 5, is reduced--21. further source of error overcome.

I have constructed a centrifugal impeller,

which is not suitable as a pump displacing volume with an eflicient consumption or power, but Ihave provided an impeller and easing which creates a pressure accurately in proportion to its speed ofrotation. This result is accomplished by means through which I confine a rotating ring of fluid which has a definite inside and outside from cylindrical shell lOto ring 5 onlyIby means of a radial flow. In consequence of having defined the external and internal diametersoi' the ring of rotating fluid, the pressure generated is made a definite quantity.

It is obvious to those skilled in the art thatmany diflerent shapes otimpeller may be employed and that a number .of' means are available-fin :the art to obtain similar results to those shown in'the embodiment of my -in,,vention,.which are accomplished by :ringowith radial perforations 3131, and shell .10 .with perforations 12- 42 and VV'hilel prefer to use both internal and external perforated-inlets and outlets, I give greater importance to r1ng5. Cylindrical shall l Omay be omitted Without introducing sages forthe yfluid flow.

serious errors in the relation between pressure and speed. The annular ring '5, or its equivalent, limits positively the outer diameter of fluid rotation and as'such a limit is an essential.

I claim:

1. In a centrifugal fluid pressure generating apparatus adapted to produce accurately a pressure in proportion to the square of thespeed of rotation, an impeller to transmit rotating velocities to a fluid andmeans to restrict the rotating fluid to a ringof deflnite internal and external diameter.

2. In a centrifugal fluid pressure generating apparatus adapted to produce accurately V a pressure in proportion to the square of the speed of rotatiommeans to impart rotating velocities with substantially complete nonconversion into pressure.

5.111 a centrifugal fluid pressure generatingapparatus, an impeller, means to introduce fluid radially in the impeller inlet and means to discharge fluid radially delivered by the impeller.

.6. In a centrifugal fluid pressure generating apparatus adapted to produce accurately a pressure inproportion to the square of the speed ofrotation, ashrou'ded impeller having perforations for radial discharge of the fluid passing through the impeller, a char ber adapted vto receive the fluid discharged by the mpeller and a stationary rlng'lo- .jcated in said chamber having radial pas- CHARLES H. SMOOT. 

